Pediatric safety profile of low titer O whole blood with increasing Anti-A and Anti-B titers

Abstract Objectives To add additional evidence to the safety of using low-titer O whole blood (LTOWB) in the massively hemorrhaging pediatric population, even with increasing allowance of anti-A and anti-B titers, up to 200. Methods A retrospective review from December 2021 to March 2023 of the blood bank and surgical massive transfusion protocols was performed with IRB approval to identify patients less than 18 years old who had received LTOWB as part of trauma resuscitation. In addition to patient characteristics, volume of LTOWB and other components were assessed, as well as Day 1-3 of serum potassium, creatinine, and total bilirubin. Wilcoxon rank-sum tests were performed to compare continuous variables and Fisher’s exact tests were performed to compare categorical variables between group O blood groups patients and non-O blood group patients. Results Only ten patients were identified under 18 years of age who had received LTOWB during trauma resuscitation, with five being blood group O and five non-O. Patient characteristics were similar between the two groups; however, only 10% were female and 10% self-reported as Black or African American. Age in the non-O group was 15 +/- 3.0 and 16.2 +/- 1.3 in the O group, p=0.75. Weight was 56.16 kg +/- 7.17 in the non-O group and 64.02+/- 14.23 in the O group, p=0.35. LTOWB transfused was 10.46 mL/kg +/- 2.42 in the non-O group and 10.32 +/- 6.53 in the O group, p=0.25. Potassium, creatinine, and total bilirubin were similar on Days 1-3 in both groups, except a single high total bilirubin in the non-O group, and this value normalized on Day 3. Conclusion A small data set was extracted from the available massive transfusion protocol data, reflecting the small amount of pediatric patients requiring massive transfusion for trauma compared to adults. Moreover, the predominance of males requiring massive transfusion for trauma corresponds with general trauma trends in the United States. These data reflect and are similar to previous safety reviews of pediatric trauma patients receiving LTOWB. This retrospective review records, however, a time period when the titer of anti-A and anti-B had been relaxed to 200 (rather than 50 in previous studies). This study, although small, reflects an additional Level I trauma site delivering LTOWB at potentially higher titers without negative sequelae in potassium, creatinine, or total bilirubin. With upcoming randomized controlled trials, such as Massive Transfusion in Children (MATIC-2), these data continue to reassure that the practice of using LTOWB is likely safe during the resuscitation period.